Industrial design of modern wireless devices is evolving towards lower profile devices. For example, many devices have thicknesses smaller than 10 mm. Additionally, modern wireless devices increasingly make use of metalized structures, such as metal rings, metal slots, and metal cases and the like. These modern wireless devices include cellular phones, tablets, or wearables such as watches, eyeglasses and virtual reality headsets or the like. Wireless devices require multiple multi-band radio frequency (RF) antennas to operate on, or near, users. Typical antennas include cellular main antennas, diversity antennas, wireless networking (e.g., WiFi, 802.11 or Bluetooth) antennas, near field antennas (e.g., near field communication or wireless charging) and global positioning (e.g., GPS) antennas. Multiple multi-band antennas have to be co-designed to cooperate with each other and with other electromagnetic components such as speakers, LCD screens, batteries, sensors, etc. However, antennas in proximity to each other result in low isolation, reduced efficiency, and increased channel interference. In some devices, a top antenna and main antenna are both used to communicate on a single band or frequency, with active antenna switches changing between the top antenna and bottom main antenna when one of antennas is obstructed by the user, for example, by the user's hand position on the device. The performance of the top antenna becomes increasingly important as it is frequently located next to other antennas such as WiFi & GPS combination antennas.